Among electronic components for input operation incorporated into various types of electronic devices, those equipped with a roller-shaped operation part have been widely used.
Hereinafter, a description is made for such a conventional component for input operation.
FIG. 12 is a sectional elevational view of a conventional component for input operation. FIG. 13 is an exploded perspective view of the component. FIG. 14 is a side sectional view of the same.
In FIGS. 12 through 14, operation part 1 is formed into a roller shape with its outside shape roughly cylindrical. The central hole of operation part 1 has central axis 2 bonded thereto. Both ends of central axis 2 protrude laterally from the round side of operation part 1. Both protrusions of central axis 2 are respectively inserted into the holes provided in the side wall of attaching member 3 and are rotatably retained. Attaching member 3 above-described is formed into a frame-like shape with two members coupled. Then, each end of above-described central axis 2 protruding outward from the above-described retaining part has ring magnet 5 (5A, 5B), formed into a cylindrical shape, fixed coaxially with operation part 1 through retainer 4.
Ring magnets 5A, 5B are identical to each other and are magnetized to north and south poles alternately at a given angular pitch. Then, ring magnets 5A, 5B are integrated with central axis 2 through retainer 4, circumferentially displaced from each other by a certain angle.
Detection elements 6A, 6B detect magnetic variation. They are respectively arranged on the inner surface of the side wall of base 7 formed into an open-topped U shape from the side view. Detection element 6A is arranged side by side with ring magnet 5A at a given spacing, aligned to the extended line of central axis 2, corresponding to above-described ring magnet 5A. Similarly, detection element 6B is arranged side by side with ring magnet 5B at a given spacing, aligned to the extended line of central axis 2, corresponding to above-described ring magnet 5B.
Frame-shaped attaching member 3 is rotatably retained by base 7. Base 7 is integrated with flexible wiring plate 9 equipped with press switch 8 activated when pressed by a protrusion provided on attaching member 3 when attaching member 3 rotates. Flexible wiring plate 9 has an extended part extended to the inner surface of the side wall of base 7. The extended part has detection elements 6A, 6B implemented thereon and a wiring part wired from press switch 8 and detection elements 6A, 6B provided.
Attaching member 3 further has elastic spring member 10 made of a leaf-spring member fixed thereto. The tip of the elastic arm of elastic spring member 10 elastically contacts the roughly central position of central axis 2 formed into a regular polygon in cross section.
A conventional component for input operation is structured as described above.
Next, a description is made for the operation of a conventional component for input operation.
First, exerting a tangential force on the outer circumferential surface of operation part 1 to rotate operation part 1 causes operation part 1 and central axis 2 bonded thereto to rotate. Consequently, ring magnets 5A, 5B at both ends integrated to central axis 2 rotate accordingly with each other. Magnetic variation generated according to the rotation is detected by corresponding detection elements 6A, 6B individually. At this moment, ring magnets 5A, 5B are fixed to central axis 2, displaced from each other by a certain angle, and thus pulse signals with a given phase difference are gained from detection elements 6A, 6B, thereby enabling rotation direction and rotation amount to be detected.
During the rotation of operation part 1, the tip of the elastic arm of elastic spring member 10 fixed to attaching member 3 elastically contacts the central part of central axis 2 formed into a regular polygon in cross section, including while central axis 2 is rotating, thus giving a certain click touch. Pressing down operation part 1 causes attaching member 3 retaining operation part 1 to rotate relatively to base 7, pressing press switch 8 arranged on base 7. The pressing generates a switching signal. Prior art documents related to the present invention include Japanese Patent Unexamined Publication No. 2005-302654.
However, a conventional component for input operation detects rotation of operation part 1 in a noncontact manner as its specification, while a click touch during rotating operation is gained by an elastic contact of elastic spring member 10 to central axis 2, thus reducing the rotation life. Further, when the central part of central axis 2 formed into a regular polygon in cross section 3 wears, a click touch given becomes dull.